Summary

Salmonella enteritidis is now the most common Salmonella serovar in many countries. We have used cloned DNA probes to analyze genome interrelationships between strains chosen to represent the current S. enteritidis pandemic, and included designated type strains of the seven subspecies of Salmonella in order to compare the levels of discrimination of probes. DNA sequence divergence and rearrangements were analyzed in and around the rfa, fim and umuDC loci, and around insertion sites of the Salmonella-specific DNA insertion element, IS200.

The S. enteritidis isolates showed a high degree of genome homogeneity. Chromosomal genetic loci exhibited characteristic DNA sequence divergence between subspecies of Salmonella, but no intraserovar divergence or difference with the subspecies I type strain was observed for S. enteritidis. The locus umuDC was not found in S. enteritidis. S. enteritidis contains a conserved and a variable site of insertion of insertion sequence IS200 and the analysis of DNA rearrangements around the second of these sites showed that three distinct evolutionary lines or races exist within pandemic isolates associated with human gasteroenteritis. IS200 profiles of a range of U.K. isolates of the epidemic phage type PT4 showed that all belonged to a single clonal line.

References

[1]
Le Minor
L.
(
1988
)
Eur. J. Clin. Microbiol. Infect. Dis.
 
7
,
214
218
.
[2]
Beltran
P.
Musser
J.M.
Helmuth
R.
Farmer
J.J.
III
Frerichs
M.
Wachsmuth
I.K.
Ferris
K.
McWhorter
A.C.
Wells
J.G.
Cravioto
A.
Selander
R.K.
(
1988
)
Proc. Natl. Acad. Sci., USA
 
85
,
7753
7757
.
[3]
Reeves
M.W.
Evins
G.M.
Heiba
A.A.
Plikaytis
B.D.
Farmer
J.J.
III
(
1989
)
J. Clin. Microbiol.
 
27
,
313
320
.
[4]
Ørskov
F.
Ørskov
I.
(
1983
)
J. Infect. Dis.
 
148
,
346
357
.
[5]
Mawer
S.L.
Spain
G.E.
Rowe
B.
(
1989
)
Lancet (ii)
 ,
280
281
.
[6]
Humphrey
T.J.
Chart
H.
Baskerville
A.
Rowe
B.
(
1991
)
Epidem. Infect.
 
106
,
33
43
.
[7]
St. Louis
M.E.
Morse
D.L.
Potter
M.E.
de Melfi
T.M.
Guzewich
J.J.
Tauxe
R.V.
Blake
P.A.
(
1988
)
j. Am. Med. Assoc.
 
259
,
2103
2107
.
[8]
Rodrigue
D.C.
Tauxe
R.V.
Rowe
B.
(
1990
)
Epidem. Infect.
 
105
,
21
27
.
[9]
Anon
(
1991
)
Update on Salmonella infection
.
P.H.L.S.-SVS Update No. 6
 .
[10]
Ward
L.R.
de Sa
J.D.M.
Rowe
B.
(
1987
)
Epidem. Infect.
 
99
,
291
294
.
[11]
Anon
(
1988
)
Lancet (ii)
 ,
720
722
.
[12]
Kakhria
R.
Duck
D.
Lior
H.
(
1991
)
Epidem. Infect.
 
106
,
25
32
.
[13]
Purcell
B.K.
Pruckler
J.
Clegg
S.
(
1987
)
J. Bacteriol.
 
169
,
5831
5834
.
[14]
Kadam
S.K.
Rehemtulla
A.
Sanderson
K.E.
(
1985
)
J. Bacteriol
 
161
,
277
284
.
[15]
Thomas
S.M.
Sedgewick
S.G.
(
1989
)
J. Bacteriol
 
171
,
5776
5882
.
[16]
Williamson
C.M.
Baird
G.D.
Manning
E.J.
(
1988
)
J. Gen Microbiol.
 
134
,
975
982
.
[17]
Hovi
M.
Sukopolvi
S.
Edwards
M.F.
Rhen
M.
(
1988
)
Microbial Path.
 
4
,
385
391
.
[18]
Gibert
I.
Carrol
K.
Hillyard
D.R.
Barbe
J.
Casadesus
J.
(
1991
)
Nucleic Acids Res.
 
19
,
1343
.
[19]
Lam
S.
Roth
J.R.
(
1983
)
Cell
 
34
,
951
960
.
[20]
Lam
S.
Roth
J.R.
(
1983
)
Genetics
 
105
,
801
811
.
[21]
Lam
S.
Roth
J.R.
(
1986
)
J. Mol. Biol.
 
187
,
157
167
.
[22]
Gibert
I.
Barb
J.
Casadesus
J.
(
1990
)
J. Gen. Microbiol.
 
136
,
2555
2560
.
[23]
Stanley
J.
Jones
C.S.
Threlfall
E.J.
(
1991
)
FEMS Microbiol. Lett.
 
82
,
83
90
.
[24]
Stanley
J.
Brown
G.G.
Verma
D.P.S.
(
1985
)
J. Bacteriol.
 
163
,
148
154
.
[25]
Upholt
W.B.
(
1977
)
Nucleic. Acids Res.
 
4
,
1257
1265
.
[26]
Pullinger
G.D.
Baird
G.D.
Williamson
C.M.
Lax
A.J.
(
1989
)
Nucleic. Acids Res.
 
17
,
7983
.
[27]
Kado
C.I.
Liu
S.-T.
(
1981
)
J. Bacteriol.
 
145
,
1365
1375
.
[28]
Crichton
P.B.
Old
D.C.
(
1990
)
J. Clin. Microbiol.
 
32
,
145
152
.
[29]
Crosa
J.H.
Brenner
D.J.
Ewing
W.H.
Falkon
S.
(
1973
)
J. Bacteriol.
 
115
,
307
315
.
[30]
Chart
H.
Threlfall
E.J.
Rowe
B.
(
1989
)
FEMS Microbiol. Lett.
 
58
,
299
304
.